The Lumi invitation link expires after 7 days. If an invitee has not accepted their invitation in that time and you need to resend it, this can be done by an Account or Project Administrator.
To manage users within a specific Project, hit the Users icon in the left-hand column.
Or to Manage Users across the whole organisation, Account Admins can select their personal avatar in the top right corner of your Lumi browser, and hit "Users" under the Account Admin section.
This opens the User Management page which has a list of all of the users in your organisation. You can see user avatars, names, email, all of the projects they have access to, their user level, and status. User status can be Invited, Active, or Deactivated.
The toolbar at the top allows you to search for any keywords or names, or filter by project, level, and status.
For users that have been invited, but have not yet accepted their invitation to Lumi, you'll see an Invited status next to them.
To resend, hit the arrow icon, to delete the invitation, hit the bin icon.